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© National Strength & Conditioning Association
Volume 23, Number 1, page 21–30
Baseball (Part I):
Dynamic Flexibility
Gregory A. Fredrick, CSCS
International Performance Institute
Bradenton, Florida
David J. Szymanski, MEd, CSCS
Department of Health and Human Performance
Auburn University
Auburn, Alabama
Keywords: dynamic flexibility; mobility; balance; warm-up
BEFORE PARTICIPATING IN A
practice session or a game, it is
common to see baseball players
performing either static (stretch
held for 10–30 seconds) or passive
stretching (an outside force or resistance provided by oneself, partner, gravity, or a weight to help
joints move through their range of
motion) before engaging in the activities of their sport, such as
throwing, fielding, or hitting. To
most baseball players these forms
of preactivity warm-up have been
taught as the appropriate way to
prepare themselves before stepping onto the diamond. However,
neither of these activities appears
to be the best approach to physiologically prepare the baseball player’s body for competition. According to Shellock and Prentice (10),
the best way to prepare for more
strenuous exercise (daily training
session or competition) is to perform specific warm-up exercises
because they provide a rehearsal
of the activity and increase body
temperature.
The purpose of this article is to
focus on the 3 components of a
February 2001
specific warm-up: cardiovascular,
neural, and dynamic flexibility,
with special attention paid to the
latter. Dynamic flexibility is an active range of motion within a full
range of motion in a joint or joints
(7). When dynamic flexibility exercises are performed in the same or
similar movement patterns that are
required in practice or game situations, they prepare both the large
muscles of the hip and back and
the smaller stabilizing muscles of
the groin, knee, and ankle (3). Described within this component will
be the scientific and theoretical
reasons why dynamic flexibility is a
more appropriate prepractice or
pregame warm-up than static
stretching. Considerations on how
to match a training or game session
with the appropriate warm-up session will also be explained and displayed in table format.
■ Dynamic Flexibility Versus
Static Stretching
Dynamic flexibility, the act of
quickly moving a joint through its
range of motion with little resistance, improves flexibility, coordiStrength and Conditioning Journal
nation, balance, proprioception,
and movement speed (6). It also
raises core body and deep muscle
temperatures, elongates active
muscles (elasticity), decreases the
inhibition of antagonist muscles,
stimulates the nervous system
(arousal), and helps to decrease
the chance of injury (3, 4, 6). Additionally, dynamic flexibility teaches running mechanics/technique
that would normally be taught
during a speed, agility, or plyometric training session. This means
that dynamic flexibility can be
used to improve running mechanics/technique independent of a
training session aimed at achieving the same goal. Thus, if a baseball player engages in different
types of training sessions, he will
receive twice the opportunity to
practice proper mechanics in
hopes of maximizing his athletic
potential by making fluid, explosive movements second nature.
Static stretches, on the other
hand, may only improve flexibility,
and will do very little physiologically to warm-up the baseball
player’s body for competition. Fur21
thermore, statically stretching before practice or competition may
even have adverse effects, such as
calming the athlete, decreasing
blood flow to previously active
muscles, and reducing the overall
strength output (5). In a study by
Purdam et al. (8), athletes were
tested on torque production during knee flexion following static or
dynamic stretching to see if there
were any significant differences in
strength output. The results
showed that static stretching produced a significant reduction in eccentric hamstring strength when
compared to dynamic stretching for
a time period lasting up to 1 hour
poststretching. The researchers believed that the reduction in eccentric strength following static stretching was due to suppression of the
central nervous system. These findings support the use of dynamic
flexibility prior to competition, and
suggest that static stretching should
be used for postcompetition cool
down.
■ Elements of a Dynamic
Warm-Up
A thorough dynamic warm-up
prior to a practice session or game
must consist of 3 components: cardiovascular, neural, and dynamic
flexibility. All 3 components are
equally important to the baseball
player to ensure the greatest potential for maximal performance in
that given dynamic session.
Figure 1.
Hand walk: (top) starting position and (bottom) ending position.
■ Cardiovascular
Physiologically, the importance of
incorporating low/moderate intensity (<75% HRmax) activities,
such as butt kicks, high knee
skips, carioca, and strides in the
prepractice or pregame warm-up
is to improve the efficiency of the
cardiovascular and respiratory
systems (4). Low/moderate intensity, continuous rhythmic activities will prepare the heart for the
22
physiological demands and processes that will soon be placed
upon it, increase blood flow to the
working muscles, as well as raise
the body core and active muscle
temperatures. In extreme weather
conditions, low/moderate intensity activities become much more
important.
When playing in cold weather,
a baseball player could lose fine
Strength and Conditioning Journal
motor skills, such as the finger
dexterity needed to catch and
throw a baseball. Also, agonist
and antagonist muscles may
begin to shiver that could further
impair a baseball player’s normal
movement patterns during a
game. Cooled muscles would ultimately lead to a decrease in
strength (2). Thus, a dynamic
warm-up including low/moderate
February 2001
Figure 2.
Inverted toe touch (opposite hand to opposite toe).
Figure 3.
Straight leg march: (left) starting and (right) ending position.
February 2001
Strength and Conditioning Journal
intensity activities would help the
baseball player better acclimate to
his environment by increasing
body core and active muscle temperatures and countering the
shivering mechanisms to generate
heat. This would make movement
patterns smoother and more fluid.
In hot weather, the temperature of the player’s peripheral tissues (i.e., skin and muscle) will
resemble the environmental temperature. Additionally, muscle
temperature is determined by
muscle blood flow, metabolic rate,
and hydration status (2). The core
23
body temperature, on the other
hand, remains relatively constant
and rises in direct proportion to
relative exercise intensity (2).
Thus, the greater the relative exercise intensity, the more core temperature will rise. Muscle temperature tends to be higher on a
warm day for a given exercise intensity than on a cool day. However, regardless of the environmental
temperature, it is still important to
perform a dynamic warm-up before practice or a game because it
increases muscle and ligament
elasticity and movement flexibility,
in addition to increasing core body
and active muscle temperatures
(7). Because these changes occur
sooner due to the high environmental temperature, less time
needs to be spent on the dynamic
warm-up (15–20 minutes) prior to
practice or a game.
■ Neural
Table 1
Movement Preparation
A. General warm-up: jog 5 min at own pace
B. Joint mobility
1. Neck rotations
7. Seated arm runs
2. Shoulder shrugs
8. Supine straight leg crossover
3. Arm circles/arm hugs
9. Press-up
4. Alternating straight
10. Calf stretch
arm swings to arm runs
11. Standing trunk twist
5. Supine bent knees crossover 12. Standing side bend
6. Prone leg over
C. General movement preparation
1. Ankle
a. Heel/toe raise
d. Toe up/toe down
b. Heel to toe walk
e. Toe tap
c. Ankle circles
f. Cocky walk with arm circles
2. Hamstrings
a. Hand walk
c. Straight leg march
b. Inverted toe touch
d. Straight leg skip
3. Quadriceps/hip flexors
a. Forward lunge with forearm to instep
b. Backward lunge
c. Butt kicks
4. Hips/groin
a. Leg cradle
d. Backwards dog and bush
b. Drop lunge
e. Lateral lunge
c. Dog and bush
D. General linear preparation
1. Knee hug lunge
4. Progressive toe up/
2. Ankle skip
knee up skip
3. Ankle flip
5. Power skip
6. Toe up/knee up run
E. General multidirectional preparation
1. Lateral/base
3. Dropstep/backpedal
a. Lateral high knee march
a. Dropstep squat
b. Lateral high knee skip
b. Dropstep skip
c. Lateral base slide
c. Backward reach run
2. Crossover
a. In-place crossover
b. Carioca
c. High knee carioca
Although the cardiovascular and
neural components are divided
into 2 separate categories in this
article, it should be noted that
many of the changes or responses
due to exercise are not solely one
or the other. In fact, the control
over circulatory and respiratory
functions are neurally regulated
via chemoreceptors, baroreceptors, and muscle afferents (1).
However, it is the purpose of this
article to discuss the neural aspects as they relate to motor unit
and muscle fiber activation.
The importance of incorporating a neural component into a
well-rounded prepractice or pregame dynamic warm-up is to raise
the level of excitation of the nervous system. According to Sale’s
(9) ramp theory of motor unit and
muscle fiber recruitment, a progressively increasing force recruits
the motor units at a gradual and
increasing level from a slow twitch
force (twitch speed) to a fast twitch
force (twitch speed). Thus, as the
baseball player goes through a
gradual progression of dynamic
warm-up exercises that become
more demanding, starting with
joint mobility exercises, then moving to general movement preparation, and finally to multidirection-
24
Strength and Conditioning Journal
al preparation (see Table 1), the
activation of more motor units will
occur. This will allow them to be
physiologically ready at game
time. In addition, the neural
warm-up component prepares the
body for the increased motor unit
recruitment of the task-depenFebruary 2001
Figure 4.
Forward lunge with forearm to instep.
dent, specific movement patterns
used by the multifunctional muscles involved (9). Simply put, there
is a different motor unit recruitment order and firing pattern for 2
different, but similar, movements
that use the same muscles (i.e., a
diagonal single leg bound versus a
diagonal lunge).
■ Dynamic Flexibility
There are numerous reasons why
incorporating a dynamic flexibility
component into a prepractice or
pregame warm-up is important.
Figure 6.
Dynamic
flexibility
improves
movement flexibility, balance, coordination, proporioception, elasticity of the muscles and ligaments, changes the surfaces of
joints in the process of long-term
flexibility training, and increases
core body and active muscle temperatures (7). Its purpose is to take
the baseball player gradually from
a resting state to practice or game
speed without fatiguing them.
Dynamic flexibility includes a
myriad of prepractice or pregame
exercises for improving joint mo-
Drop lunge (carioca step behind).
February 2001
Figure 7.
Figure 5.
Leg cradle. While walking,
leg is crossed in front of
body and gently lifted by
foot and ankle. Repeat
with the other leg.
Prone leg over. Alternate touching toe to opposite side of body. Repeat with other foot.
Strength and Conditioning Journal
25
cal day, as well as a cold day would
require a longer warm-up session.
An endurance-based or low technical day, as well as a hot and
humid day, would require a shorter warm-up session (4). The intensity of the session is based on both
the type of training to be emphasized and the environmental conditions. On a power day, dynamic
flexibility should be more intense.
That is, it should include more
ground contacts or impacts, such
as skipping to increase neural
stimulation. On a preparation or
regeneration day (low intensity,
decreased volume), dynamic flexibility should be less intense and
include more walking and lunging
exercises. The movements should
be performed in a continuous and
Figure 8.
“down and back” fashion over
15–20 yards.
The dynamic flexibility warmup should mirror the days’ training objective or competition. It
should prepare the baseball player to be able to optimally achieve
that days’ training goal and be
sport specific to baseball movements. Whether the days’ training
focus is predominately linear, lateral, or multidirectional, the dynamic warm-up should mimic
that goal. Baseball is multidirectional, thus the dynamic warmup should include all 3 aspects of
movement. It should be noted
that regardless of the training
focus or game preparation, all dynamic warm-ups should contain
and begin with joint mobility.
Cocky walk with arm cir
cles. Ball of foot is snapped
down while walking and
performing arm circles.
Heels do not touch ground.
Palms of hands face up.
bility and muscle and ligament
elasticity. It can be further subdivided into 4 groups: joint mobility,
general movement preparation,
general linear preparation, and
general multidirectional preparation. Table 1 lists these groups,
along with a number of exercises
contained within each group. Figures 1–14 demonstrate some of
these movements.
■ How to Implement
The entire dynamic warm-up session should take about 15–20
minutes but can go as long as 35
or 40 minutes depending on the
environmental temperature. The
length of the session is also determined by the emphasis of the
training day. For instance, a
speed, strength, or highly techni26
Figure 9.
Dog and bush: (left) knee is raised laterally to waist height, and (right)
adducted to midline of body, then lowered to ground. Repeat with other
leg.
Strength and Conditioning Journal
February 2001
Table 2
Training Day Planner
H M
x x
x x
x x
x x
L
x
x
x
x
P
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Joint mobility
Neck rotations
Shoulder shrugs
Arm circles/arm hugs
Alternating straight
arm swings to arm runs
Supine bent knees crossover
Prone leg over
Seated arm runs
Supine straight leg crossover
Pressup
Calf stretch
Standing trunk twist
Standing side bend
General movement preparation
H M L P Ankle
x x
Heel/toe raise
x x x
Heel to toe walk
x x x x
Ankle circles
x
x
Toe up/toe down
x
x
Toe tap
x x x x
Cocky walk with arm circles
H M
x x
x x
x x
x x
L
x
x
H M
x x
x
x x
L
x
x
H M
x x
x x
x x
x
x
L
x
x
P
x
x
P
x
x
P
x
x
x
Hamstring
Hand walk
Inverted toe touch
Straight leg march
Straight leg skip
General linear preparation
Knee hug lunge
Angle skip
Ankle flip
Progressive toe up/knee up skip
Power skip
Toe up/knee up run
H M L
x
x
x x x
x x x
x x
x x
x
x
General multidirectional preparation
Lateral/base
H M L
Lateral high knee march
x x x
Lateral high knee skip
x x
Lateral base slide
x x
P
x
x
x
P
x
x
Crossover
In-place crossover
Carioca
High knee carioca
H M L
x x x
x
x
x
P
Dropstep/Backpedal
Dropstep squat
Dropstep skip
Backward reach run
H M L
x x x
x
x
x
x
P
Total
45 33 26 32
x
x
Quadriceps/hip flexors
Forward lunge with forearm to instep
Backward lunge
Butt kicks
Hips/groin
Leg cradle
Drop lunge
Dog and bush
Backward dog and bush
Lateral lunge
H = high intensity, M = medium intensity, L = low intensity, P = pre-event.
Table 2 lists which exercises and
how many exercises are to be
done when considering the training days’ objective (high, medium,
or low intensity, or pre-event).
February 2001
■ Conclusion
Many performance coaches believe
that the key to obtaining an optimal
training or game performance is to
Strength and Conditioning Journal
train sport specific. With this in
mind, it makes sense to warm-up
dynamically prior to a practice or a
game, and to cool down statically afterward. This point is argued well by
27
Figure 10.
Lateral lunge with both feet pointed forward. Keep weight on heel of
lead foot so knee does not extend over toes.
Figure 11.
Power skip is performed by raising opposite arm
and leg. Emphasize height and powerful down
ward action of raised leg.
28
Figure 12.
Gambetta (5), who states, “…static
stretches before warm-up or competition can actually cause tiredness
and decrease coordination. In addition, static stretching improves static flexibility, while dynamic stretching improves dynamic flexibility;
therefore, it is not logical to use static stretches to warm-up for dynamic actions.” Simply stated, dynamically warming up prior to practice or
competition will enable baseball
players to have a greater dynamic
range of motion in sport specific
movements.
Dynamic flexibility physiologically prepares the athlete for practice or a game. It can be an enjoyable way for athletes to get
High knee carioca. After raising knee high, emphasize a powerful downward action of the
foot.
Strength and Conditioning Journal
February 2001
Figure 13.
Dropstep squat. Start in (left) normal position, then (center) abduct hip laterally and take a dropstep backwards,
finally (right) performing a standing squat. Repeat with opposite leg.
emotionally and psychologically
ready to play, or even calm those
athletes who become nervous before competition. Finally, it can
serve as a speed mechanic/technique and movement teaching tool.
Give dynamic flexibility a try, be
creative, and use a variety of movements to avoid redundancy. ▲
3.
■ References
1. Brooks, G.A., T.D. Fahey,
and T.P. White. Circulation
and its control. In: Exercise
Physiology: Human Bioenergetics and Its Applications.
Mountain View, CA: Mayfield
Publishing Company, 1996.
pp. 260–278.
2. Brooks, G.A., T.D. Fahey,
and T.P. White. Exercise in
February 2001
4.
5.
6.
the heat and cold. In: Exercise Physiology: Human Bioenergetics and Its Applications. Mountain View, CA:
Mayfield Publishing Company, 1996. pp. 428–450.
Coleman, A.E. A baseball
conditioning program for all
seasons. In: Injuries in Baseball. Philadelphia, PA: Lippincott-Raven Publishers, 1998.
p. 537–545.
Gambetta, V. Get ready, get
set. Training Cond. 9(2):19–21.
1999.
Gambetta, V. Stretching the
truth. Training Cond. 7(2):
25–31. 1997.
Kurz, T. Science of Sport Training: How to Plan and Control
Training for Peak Performance.
Strength and Conditioning Journal
Island Pond, VT: Stadion,
1991.
7. Kurz, T. Stretching Scientifically: A Guide to Flexibility
Training (3rd ed.). Island
Pond, VT: Stadion, 1994.
8. Purdam, C., A. Davies, K.
Finley, and M. Hilly. A comparison of the effect of static
and ballistic stretching on
hamstring strength. The
Muscle Symposium Book of
Proceedings: Scientific and
Clinical Aspects of Exercise,
Injury, and Recovery. Australian Institute of Sport.
April 1999.
9. Sale, D.G. Influence of exercise and training on motor
unit activation. Exerc. Sport
Sci. Rev. 15:95–151. 1987.
29
Figure 14.
Backward reach run. First, (left) raise the heel to the buttocks to backpedal, then (right) extend knee and reach foot
back.
10. Shellock, F.G., and W.E.
Prentice. Warming-up and
stretching for improved physical performance and prevention of sports-related injuries.
Sports Med. 2(4):267–278.
1985.
Fredrick
30
Gregory A. Fredrick, CSCS is a
performance specialist at the International Performance Institute
in Bradenton, Florida. Before joining the staff at IPI, he served as a
graduate assistant strength &
conditioning coach at Auburn
University, interned as a strength
and conditioning coach with the
Hampton Roads Mariners Professional Soccer Club, and was a student assistant strength and conditioning coach at the University of
Tennessee. He is also a Certified
Club Coach through U.S.A.
Weightlifting.
David J. Szymanski, MEd, CSCS
is the baseball exercise physiologist and a doctoral candidate in
the Department of Health and
Human Performance at Auburn
University. He has a masters in PE
from Southwest Texas State University and previously was the assistant baseball coach and conditioning coordinator at Texas
Lutheran University.
Szymanski
Strength and Conditioning Journal
February 2001
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